Hi, I'm having a problem with my '95 F150 (sorry about the title saying '96). After getting the rear yoke removed to take out the drive shaft and change the U-joints, the slip yoke initially would slide back and forth only very slightly, but then no further. Pushing and pulling back and forth, harder and harder, while wiping the grease away as the splines began to show, I got it moved to a point where about 5/16" of the splines are visible. I stuck a screw driver through the rear yoke and used it to push on with my feet. I probably put 50 pounds of pressure on it, but the yoke doesn't slide one wit further out, although it still slides easily forward" all the way, then back, stopping at the same point. It seems to be in some sort of vacuum lock, due to copious amounts of grease. I tried to pump more grease into it, with pressure on the drive shaft, thinking additional grease might help force it out, but the grease just squirted out from the splines that were showing, so I immediately stopped. I tried removing grease zerk, but that didn't help. In 47 years of working on vehicles, I've never experienced this happening, or even heard of it. I've tried hammering on the front yoke, too, with no further movement. It does seem that the slip yoke is in some sort of vacuum lock. I'm thinking to drill a hole into the slip yoke, somewhere near where the male spline piece bottom outs, in hopes of allowing air to get in and remove the vacuum, but am sure I should haven't to do this, and would have to at best make an educated guess on the right location, anyway. Besides, I'd much rather not go to the trouble of possibly screwing up the slip yoke. Has anyone ever had this happen to them? Any ideas for a solution? Thanks in advance!

 

Apparently, the vacuum was the problem - solved by positioning myself better so that I could put more pressure on the yoke. It then snapped right out! Thanks to all the people who were going to give me this solution!